Welcome to the SeeMeCNC Community

I really like everything I have seen on the Rostock MAX v2 here, but one thing that is not completely obvious is whether or not the hot end will achieve temperatures conducive to printing in PC. If not then will this require an extruder swap? If so does anyone have suggestions?

Thanks!!!!

I'm not aware of the temps needed for the material you're talking about, but I can tell you the the SeeMeCNC hotend uses PEEK plastic as an insulator. Without cooling (and caution) your maximum temp would be the melting point of PEEK, which I recall is somewhere in the 140's.

Wikipedia knows: "PEEK has a glass transition temperature of around 143 °C (289 °F)"
http://en.wikipedia.org/wiki/PEEK#Properties

Glass transition temperature is not the melting point, that's merely the temperature at which the structural/molecular makeup of the material transitions to a glass state. The max temperature of the stock hot end is 240C. If you want to print in polycarb, you need an all metal hotend, you need temperatures of about 300C to print it.

True... I misspoke. We all agree that it's a good place to define the maximum working temp of that material though, right?


Get the E3D if you need higher temps.

I have been testing a polycarb (I think it's a mix, not pure polycarbonate) and it'll extrude as low as 220º but it really needs 270º to form a decent layer bond, in which case you couldn't run it through the stock hot-end. Perhaps with a more powerful PEEK fan, but it'd be risky I would bet.

You won't get good results with PC and the stock Hotend, I'd probably try an E3D.
The gotcha with PC outside the high temp requirements is it is extremely hygroscopic, and once the water is absorbed it doesn't print clear, one test I saw, showed a difference in clarity between the day it was unpacked and the following day.

Thanks for the information! That E3D is the best deal I have seen. Thank you again!

Polygonhell wrote:You won't get good results with PC and the stock Hotend, I'd probably try an E3D.
The gotcha with PC outside the high temp requirements is it is extremely hygroscopic, and once the water is absorbed it doesn't print clear, one test I saw, showed a difference in clarity between the day it was unpacked and the following day.

Interesting, perhaps this explains the sparkly finish I currently have... I'll try drying for a few days and see if that helps...

Yup, it collects water fast and drastically affects printing.

The PC I am using is from ultimachine. I have found it really prints best at very high temps especially with smaller nozzle sizes. 280-300 for .25, 265-280 for .4.

Well I'm drying mine out some more and I'll try again!

Not that I minded the sparklies....

Polygonhell wrote:You won't get good results with PC and the stock Hotend, I'd probably try an E3D.
The gotcha with PC outside the high temp requirements is it is extremely hygroscopic, and once the water is absorbed it doesn't print clear, one test I saw, showed a difference in clarity between the day it was unpacked and the following day.

Thanks for your expertise! Are the E3D all metal hotends interchangeable on the Rostock Max v2? Any new developments on the PC print front?

Thanks again!!

Prior to printing with PC I always pre-dry it in an oven overnight before use. Really helps it be less problematic the next day during printing.

As far as drying temps for the oven go, it will vary from brand to brand so my numbers will not really be helpful to you and your area. But Ultimachine PC in a very dry none humid environment I will predry my PC at around 120-150f for 12 hours min.

Flateric wrote:Prior to printing with PC I always pre-dry it in an oven overnight before use. Really helps it be less problematic the next day during printing.

As far as drying temps for the oven go, it will vary from brand to brand so my numbers will not really be helpful to you and your area. But Ultimachine PC in a very dry none humid environment I will predry my PC at around 120-150f for 12 hours min.

Thanks Flateric!!! I will follow up with my findings as well when they become available If you don't mind me asking, which hotend are you using, and was it interchangeable with the Rostock Max V2 stock hotend?

I'm a big fan (punny) of a properly cooled E3D hotend.

As far as being interchangable, not entirely sure what you mean, does it fit easily? Yes. Is it easy to hook up in a similar way to the stock hotend? Yes. Do you have to be a little more careful about printing with PLA? Absolutely, don't let it sit in the hotend at temp, always pre-prime pre-feed just prior to printing and retract out before allowing to cool when your done for the day, or night.

Polycarbonate and nylon are pretty similar for printing. They both extrude at 220 degrees C, but they don't bond layers very well below 250 C. The higher the temperature, the stronger the part. 280 degrees makes indestructible nylon parts. I think polycarbonate needs even higher temperatures, perhaps around 290 C.


Polycarbonate is clear and rigid. Nylon is translucent and flexible. I use trimmer line a lot because it's the cheapest filament on the market, it never jams, and it's very consistent in diameter.

However I'd like a more rigid plastic, and polycarbonate is usually stiffer.


When are we going to see glass filled polycarbonate for sale as filament?!

PC on the stock hotend is just not going to happen. You also have to watch out on long print as PC can go from dry to "wet" and clouded within a long print time. For this reason i am enclosing my whole printer from the print surface to above the filament area. Also setting up an Arduino controlled system with a dehumidifier and heater (heater for ABS mostly). I will be posting a few details in a new thread shortly but a few renders are on my build page at http://forum.seemecnc.com/viewtopic.php ... 3&start=30. PC is the main reason i bought my Max and I knew from the start I would have to enclose it from head to toe. When printed dry PC is amazing stuff. But it gets wet so fast down here in Houston.

Flateric wrote:I'm a big fan (punny) of a properly cooled E3D hotend.

As far as being interchangable, not entirely sure what you mean, does it fit easily? Yes. Is it easy to hook up in a similar way to the stock hotend? Yes. Do you have to be a little more careful about printing with PLA? Absolutely, don't let it sit in the hotend at temp, always pre-prime pre-feed just prior to printing and retract out before allowing to cool when your done for the day, or night.

In terms of interchangeable, I was referring to what if any modifications to the Rostock Max V2 assembly to you made in order to accommodate/retrofit the E3D hotend, but it sounds like you just swapped one for the other.

Thanks for the info! Really looking forward to getting this thing going... And checking out that dehumidifier system

I am about to start prototyping the dehumidifier system in CAD this week. I just ordered my CNC mill so I got a bit distracted by that and getting the end mills and such I need to get a few other projects off the ground. But I should have a CAD render shortly and will be picking up the BETA version parts over the weekend.

Hey Guys! Its been a little while, but I got the Rostock kit, built it, and tested it. It makes really great parts! Now Im ready to upgrade the hotend so I can print in PC. While Im waiting for the E3D V6 to arrive I thought it might be good to return to this thread to better prepare for the PC print experience... SO a couple of preemptive questions come to mind:

1) Settings (Nozzle/Bed Temp, Feed Rate, etc)?

2) Preferred Filament?

3) Is anyone using the External ThermoCouple & external serial adapter to calibrate to +400 degrees?

4) Bed Adhesion? - I saw a thread on this, but it was incomplete. At higher bed temps or with PC does the disappearing purple not work?

Thanks!!!